@propelinc/parser

TypeScript ESLint Parser

An ESLint custom parser which leverages TypeScript ESTree to allow for ESLint to lint TypeScript source code.

Installation:

npm install @typescript-eslint/parser --save-dev

Usage

In your ESLint configuration file, set the parser property:

{
  "parser": "@typescript-eslint/parser"
}

There is sometimes an incorrect assumption that the parser itself is what does everything necessary to facilitate the use of ESLint with TypeScript. In actuality, it is the combination of the parser and one or more plugins which allow you to maximize your usage of ESLint with TypeScript.

For example, once this parser successfully produces an AST for the TypeScript source code, it might well contain some information which simply does not exist in a standard JavaScript context, such as the data for a TypeScript-specific construct, like an interface.

The core rules built into ESLint, such as indent have no knowledge of such constructs, so it is impossible to expect them to work out of the box with them.

Instead, you also need to make use of one more plugins which will add or extend rules with TypeScript-specific features.

By far the most common case will be installing the @typescript-eslint/eslint-plugin plugin, but there are also other relevant options available such a @typescript-eslint/eslint-plugin-tslint.

Configuration

The following additional configuration options are available by specifying them in parserOptions in your ESLint configuration file.

• ecmaFeatures.jsx - default false. Enable parsing JSX when true. More details can be found here.

  • It's false on *.ts files regardless of this option.
  • It's true on *.tsx files regardless of this option.
  • Otherwise, it respects this option.

• useJSXTextNode - default true. Please set false if you use this parser on ESLint v4. If this is false, the parser creates the AST of JSX texts as the legacy style.

• project - default undefined. This option allows you to provide a path to your project's tsconfig.json. This setting is required if you want to use rules which require type information. You may want to use this setting in tandem with the tsconfigRootDir option below.

• tsconfigRootDir - default undefined. This option allows you to provide the root directory for relative tsconfig paths specified in the project option above.

• extraFileExtensions - default undefined. This option allows you to provide one or more additional file extensions which should be considered in the TypeScript Program compilation. E.g. a .vue file

• warnOnUnsupportedTypeScriptVersion - default true. This option allows you to toggle the warning that the parser will give you if you use a version of TypeScript which is not explicitly supported

.eslintrc.json

{
  "parser": "@typescript-eslint/parser",
  "parserOptions": {
    "ecmaFeatures": {
      "jsx": true
    },
    "useJSXTextNode": true,
    "project": "./tsconfig.json",
    "tsconfigRootDir": "../../",
    "extraFileExtensions": [".vue"]
  }
}

Supported TypeScript Version

Please see https://github.com/typescript-eslint/typescript-eslint for the supported TypeScript version.

Please ensure that you are using a supported version before submitting any issues/bug reports.

Reporting Issues

Please use the @typescript-eslint/parser issue template when creating your issue and fill out the information requested as best you can. This will really help us when looking into your issue.

License

TypeScript ESLint Parser is licensed under a permissive BSD 2-clause license.